Error: #error This file requires compiler and library support for ISO C 2011 standard. This support is currently experimental, and must be enabled with the -std=c11 or -std=gnu11 compiler. C ISO/IEC N3337 3.11 Alignment.75 4 Standardconversions 77.
News 2018-10-13: The C Standard Library Issues List (Revision 112) is available News 2018-04-12: The C Standard Core Language Issues List (Revision 100) is available ISO/IEC JTC1/SC22/WG21 is the international standardization working group for the programming language C. Published standards and technical reports include. This file requires compiler and library support for the ISO C 2011 standard. This support is currently experimental, and must be enabled with the -std=c11 or -std=gnu11 compiler options. I remember while installing codeblocks I installed only gnu c/c compiler.
C++, one of the most popular programming languages, used in everything from Web browsers to 3D video games, has been fully updated and published as, ISO 14882:2011, Information technology – Programming languages – C++.
ISO 14882:2011 defines the programming language and specifies requirements for implementation. Also known as C++11, this is the first major revision of the standard since 1998. Its new features extend C++’s traditional strengths of flexibility and efficiency – for example, lambda functions and move semantics. Variadic templates further enable developers to use powerful expressiveness and strong abstraction to write efficient, high-performance code with full access to the hardware available when needed. Even more, the new C++11 has the convenience and ease of use of other modern languages – from features like auto type deduction and explicit virtual override control, to standard smart pointers.
According to Herb Sutter, Convener of the ISO working group that developed the standard, industry has paid more attention in recent years to “newer” managed-code environments like Java that emphasize programmer convenience at the expense of expressive power and performance, for example, by requiring always-on garbage collection, metadata for reflection, and virtual machine execution that incur a performance expense even when they’re not needed or used.
Mr. Sutter says, “Those languages continue to have their place. However, ‘traditional’ programming using native languages like C++, which emphasize expressive power and a pay-as-you-go philosophy of avoiding performance overheads unless features are actually used in the program, never really went away – and now with C++11’s improvements that incorporate many of the best features of managed languages, modern C++ code is as clean and safe as code written in other modern languages, as well as fast with performance by default and full access to the underlying system whenever you need it.
“This new edition underlines the continued importance of this popular language, whose new features and increased performance are causing renewed excitement in the industry. C++ continues to be used for just about everything, including for building compilers and runtimes for competing languages, Web browsers like Google’s Chrome, social media platforms like Facebook, and operating systems like Windows.”
C++ is a general purpose programming language based on the C programming language. In addition to the facilities provided by C, C++ provides additional data types, classes, templates, exceptions, namespaces, operator overloading, function name overloading, references, free store management operators, and additional library facilities.
“C++ remains one of the most valuable tools at the disposal of developers, and is the language of choice for demanding applications in almost every domain,” says Mr. Sutter. “With this new edition, users will benefit from the joint effort of experts from all over the world, who worked together to develop an updated and better International Standard that harmonizes and disseminates best practice.”
ISO 14882:2011, Information technology – Programming languages – C++, is available from the ANSI e-Standards Store.
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2 Language Standards Supported by GCC
For each language compiled by GCC for which there is a standard, GCCattempts to follow one or more versions of that standard, possiblywith some exceptions, and possibly with some extensions.
2.1 C Language
The original ANSI C standard (X3.159-1989) was ratified in 1989 andpublished in 1990. This standard was ratified as an ISO standard(ISO/IEC 9899:1990) later in 1990. There were no technicaldifferences between these publications, although the sections of theANSI standard were renumbered and became clauses in the ISO standard.The ANSIstandard, but not the ISO standard, also came with a Rationaledocument. This standard, in both its forms, is commonly known as C89, oroccasionally as C90, from the dates of ratification.To select this standard in GCC, use one of the options-ansi, -std=c90 or -std=iso9899:1990; to obtainall the diagnostics required by the standard, you should also specify-pedantic (or -pedantic-errors if you want them to beerrors rather than warnings). See OptionsControlling C Dialect.
Errors in the 1990 ISO C standard were corrected in two TechnicalCorrigenda published in 1994 and 1996. GCC does not support theuncorrected version.
An amendment to the 1990 standard was published in 1995. Thisamendment added digraphs and __STDC_VERSION__ to the language,but otherwise concerned the library. This amendment is commonly knownas AMD1; the amended standard is sometimes known as C94 orC95. To select this standard in GCC, use the option-std=iso9899:199409 (with, as for other standard versions,-pedantic to receive all required diagnostics).
A new edition of the ISO C standard was published in 1999 as ISO/IEC9899:1999, and is commonly known as C99. (While indevelopment, drafts of this standard version were referred to asC9X.) GCC has substantiallycomplete support for this standard version; seehttp://gcc.gnu.org/c99status.html for details. To select thisstandard, use -std=c99 or -std=iso9899:1999.
Errors in the 1999 ISO C standard were corrected in three TechnicalCorrigenda published in 2001, 2004 and 2007. GCC does not support theuncorrected version.
A fourth version of the C standard, known as C11, was publishedin 2011 as ISO/IEC 9899:2011. (While in development, drafts of thisstandard version were referred to as C1X.)GCC has substantially complete supportfor this standard, enabled with -std=c11 or-std=iso9899:2011. A version with corrections integrated wasprepared in 2017 and published in 2018 as ISO/IEC 9899:2018; it isknown as C17 and is supported with -std=c17 or-std=iso9899:2017; the corrections are also applied with-std=c11, and the only difference between the options is thevalue of __STDC_VERSION__.
A further version of the C standard, known as C2X, is underdevelopment; experimental and incomplete support for this is enabledwith -std=c2x.
By default, GCC provides some extensions to the C language that, onrare occasions conflict with the C standard. See Extensions to the C Language Family. Some features that are part of the C99 standardare accepted as extensions in C90 mode, and some features that are partof the C11 standard are accepted as extensions in C90 and C99 modes.Use of the-std options listed above disables these extensions wherethey conflict with the C standard version selected. You may alsoselect an extended version of the C language explicitly with-std=gnu90 (for C90 with GNU extensions), -std=gnu99(for C99 with GNU extensions) or -std=gnu11 (for C11 with GNUextensions).
The default, if no C language dialect options are given,is -std=gnu17.
The ISO C standard defines (in clause 4) two classes of conformingimplementation. A conforming hosted implementation supports thewhole standard including all the library facilities; a conformingfreestanding implementation is only required to provide certainlibrary facilities: those in <float.h>, <limits.h>,<stdarg.h>, and <stddef.h>; since AMD1, also those in<iso646.h>; since C99, also those in <stdbool.h> and<stdint.h>; and since C11, also those in <stdalign.h>and <stdnoreturn.h>. In addition, complex types, added in C99, are notrequired for freestanding implementations.
The standard also defines two environments for programs, afreestanding environment, required of all implementations andwhich may not have library facilities beyond those required offreestanding implementations, where the handling of program startupand termination are implementation-defined; and a hostedenvironment, which is not required, in which all the libraryfacilities are provided and startup is through a function intmain (void) or int main (int, char *[]). An OS kernel is an exampleof a program running in a freestanding environment; a program using the facilities of anoperating system is an example of a program running in a hosted environment.
GCC aims towards being usable as a conforming freestandingimplementation, or as the compiler for a conforming hostedimplementation. By default, it acts as the compiler for a hostedimplementation, defining __STDC_HOSTED__ as 1 andpresuming that when the names of ISO C functions are used, they havethe semantics defined in the standard. To make it act as a conformingfreestanding implementation for a freestanding environment, use theoption -ffreestanding; it then defines__STDC_HOSTED__ to 0 and does not make assumptions about themeanings of function names from the standard library, with exceptionsnoted below. To build an OS kernel, you may well still need to makeyour own arrangements for linking and startup.See Options Controlling C Dialect.
GCC does not provide the library facilities required only of hostedimplementations, nor yet all the facilities required by C99 offreestanding implementations on all platforms. To use the facilities of a hostedenvironment, you need to find them elsewhere (for example, in theGNU C library). See Standard Libraries.
Most of the compiler support routines used by GCC are present inlibgcc, but there are a few exceptions. GCC requires thefreestanding environment provide memcpy, memmove,memset and memcmp.Finally, if __builtin_trap is used, and the target doesnot implement the trap pattern, then GCC emits a callto abort.
For references to Technical Corrigenda, Rationale documents andinformation concerning the history of C that is available online, seehttp://gcc.gnu.org/readings.html
2.2 C++ Language
GCC supports the original ISO C++ standard published in 1998,and the 2011 and 2014 revisions.
The original ISO C++ standard was published as the ISO standard (ISO/IEC14882:1998) and amended by a Technical Corrigenda published in 2003(ISO/IEC 14882:2003). These standards are referred to as C++98 andC++03, respectively. GCC implements the majority of C++98 (exportis a notable exception) and most of the changes in C++03. To selectthis standard in GCC, use one of the options -ansi,-std=c++98, or -std=c++03; to obtain all the diagnosticsrequired by the standard, you should also specify -pedantic (or-pedantic-errors if you want them to be errors rather thanwarnings).
A revised ISO C++ standard was published in 2011 as ISO/IEC14882:2011, and is referred to as C++11; before its publication it wascommonly referred to as C++0x. C++11 contains several changes to theC++ language, all of which have been implemented in GCC. For detailssee https://gcc.gnu.org/projects/cxx-status.html#cxx11.To select this standard in GCC, use the option -std=c++11.
Another revised ISO C++ standard was published in 2014 as ISO/IEC14882:2014, and is referred to as C++14; before its publication it wassometimes referred to as C++1y. C++14 contains several furtherchanges to the C++ language, all of which have been implemented in GCC.For details see https://gcc.gnu.org/projects/cxx-status.html#cxx14.To select this standard in GCC, use the option -std=c++14.
The C++ language was further revised in 2017 and ISO/IEC 14882:2017 waspublished. This is referred to as C++17, and before publication wasoften referred to as C++1z. GCC supports all the changes in the newspecification. For further details seehttps://gcc.gnu.org/projects/cxx-status.html#cxx1z. Use the option-std=c++17 to select this variant of C++.
More information about the C++ standards is available on the ISO C++committee’s web site at http://www.open-std.org/jtc1/sc22/wg21/.
To obtain all the diagnostics required by any of the standard versionsdescribed above you should specify -pedanticor -pedantic-errors, otherwise GCC will allow some non-ISO C++features as extensions. See Warning Options.
By default, GCC also provides some additional extensions to the C++ languagethat on rare occasions conflict with the C++ standard. See Options Controlling C++ Dialect. Use of the-std options listed above disables these extensions where theythey conflict with the C++ standard version selected. You may alsoselect an extended version of the C++ language explicitly with-std=gnu++98 (for C++98 with GNU extensions), or-std=gnu++11 (for C++11 with GNU extensions), or-std=gnu++14 (for C++14 with GNU extensions), or-std=gnu++17 (for C++17 with GNU extensions).
The default, ifno C++ language dialect options are given, is -std=gnu++17.
2.3 Objective-C and Objective-C++ Languages
GCC supports “traditional” Objective-C (also known as “Objective-C1.0”) and contains support for the Objective-C exception andsynchronization syntax. It has also support for a number of“Objective-C 2.0” language extensions, including properties, fastenumeration (only for Objective-C), method attributes and the@optional and @required keywords in protocols. GCC supportsObjective-C++ and features available in Objective-C are also availablein Objective-C++.
GCC by default uses the GNU Objective-C runtime library, which is partof GCC and is not the same as the Apple/NeXT Objective-C runtimelibrary used on Apple systems. There are a number of differencesdocumented in this manual. The options -fgnu-runtime and-fnext-runtime allow you to switch between producing outputthat works with the GNU Objective-C runtime library and output thatworks with the Apple/NeXT Objective-C runtime library.
There is no formal written standard for Objective-C or Objective-C++.The authoritative manual on traditional Objective-C (1.0) is“Object-Oriented Programming and the Objective-C Language”:http://www.gnustep.org/resources/documentation/ObjectivCBook.pdfis the original NeXTstep document.
The Objective-C exception and synchronization syntax (that is, thekeywords @try, @throw, @catch,@finally and @synchronized) issupported by GCC and is enabled with the option-fobjc-exceptions. The syntax is briefly documented in thismanual and in the Objective-C 2.0 manuals from Apple.
Iso C++ 2011 Standard Dev C++
The Objective-C 2.0 language extensions and features are automaticallyenabled; they include properties (via the @property,@synthesize and@dynamic keywords), fast enumeration (not available inObjective-C++), attributes for methods (such as deprecated,noreturn, sentinel, format),the unused attribute for method arguments, the@package keyword for instance variables and the @optional and@required keywords in protocols. You can disable all theseObjective-C 2.0 language extensions with the option-fobjc-std=objc1, which causes the compiler to recognize thesame Objective-C language syntax recognized by GCC 4.0, and to producean error if one of the new features is used.
GCC has currently no support for non-fragile instance variables.
The authoritative manual on Objective-C 2.0 is available from Apple:
For more information concerning the history of Objective-C that isavailable online, see http://gcc.gnu.org/readings.html
2.4 Go Language
As of the GCC 4.7.1 release, GCC supports the Go 1 language standard,described at https://golang.org/doc/go1.
2.5 HSA Intermediate Language (HSAIL)
GCC can compile the binary representation (BRIG) of the HSAIL text format asdescribed in HSA Programmer’s Reference Manual version 1.0.1. Thiscapability is typically utilized to implement the HSA runtime API’s HSAIL finalization extension for a gcc supported processor. HSA standards arefreely available at http://www.hsafoundation.com/standards/.
2.6 D language
C++ Iso Standard Pdf
GCC supports the D 2.0 programming language. The D language itself iscurrently defined by its reference implementation and supporting languagespecification, described at https://dlang.org/spec/spec.html.
2.7 References for Other Languages
See About This Guide in GNAT Reference Manual, for information on standardconformance and compatibility of the Ada compiler.
See Standards in The GNU Fortran Compiler, for detailsof standards supported by GNU Fortran.
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